What we doCombined Sewer Overflow (CSO) Monitoring helps to ensure that regulatory requirements related to overflow consents are met.

Combined sewers transport wastewater and stormwater runoff to treatment plants. However, intense or prolonged rainfall can overload them. Combined Sewer Overflows (CSO) divert excess flow enabling plants to continue operating and preventing upstream flooding of properties. Consequently, untreated water is diverted and discharged into the environment with potential adverse health and environmental impacts.

Monitoring CSOs provides operators with an early warning of when there is a risk of a breach and enables teams to respond in real time to identify and clear blockages, construct forecasting models to improve network performance and optimise operational maintenance by observing trends in the CSO.

James Teale
Commercial Manager
t: 01132 019700 | e: jteale@ietg.co.uk
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How we do it

Our inspection process involves detailed measurement of the chamber layout which ensures the operation of the overflow is understood and that alarms are set at correct levels. Our experienced planners and schedulers conduct effective traffic permitting and route planning to ensure there are no wasted visits with associated costs.

Access issues are particularly important in relation to Combined Sewer Overflow Monitoring so we conduct full off-road walk rounds.

At IETG we conduct end to end testing and commissioning by executing a dial out and alarm test on a false spill at each site. We can remotely configure alarm thresholds and perform onsite calibration of depth and communications checks back to base.


Our extensive experience enables us to minimise the number of false alarms by choosing the best possible location for the device.

Our Data Analysts check data and communication daily, offer customers detailed reviews and mobilise teams to site as required.

This can provide a back-up to a client’s own checks and has prevented spills and alerted clients to operational problems on numerous occasions.

Our aim is to use the best available technology for the client’s needs, whether that is detailed time series data for event duration monitoring and trend analysis, or a simple, low-cost on/off alarm system to give extensive network visibility of potential spills/flooding.


Why choose IETG?What sets IETG apart?

We pride ourselves on being able to deliver a high quality service and meet clients’ delivery requirements without compromise by focusing on:-

  • Safety – Our culture is one of “We Will Work Safely or Not At All”: essential when our work is often on the highway, in confined spaces or next to watercourses.
  • Quality – Every project we deliver is subject to our rigorous Quality Control processes, which are managed by our experienced team.
  • Service – Our clients are allocated a dedicated Project Manager with proven industry experience. We pride ourselves on delivering one stop shop solutions and finding creative answers to the range of challenges projects undoubtedly throw up.
  • Value – By utilising the very latest technology, thorough planning and experienced teams, IETG provide the best solutions for all our clients needs.

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